My H also refused to communicate by e-mail. I think he didn't want a written record of what horrible things he says to me and there is also no pay off if he can't see or hear my reaction.
I read an interesting article on the net about divorcing a narcissist. It said to prepare for it to get dirty and that unfortunately you have to sink to their level and fight dirty as well or you will be run over by a freight train. Supposedly narcissists back off if you stand up and fight.
I tested this theory on Friday. H was hurling verbal abuse on the phone, making threats about the divorce (telling me he would take everything, etc.) I did what the article said and fought dirty. The article said to attack everything that he thinks makes him special. I said he was boring. His friends all laugh at him behind his back. Everyone thinks he is a joke.
It worked. He backed off (and he started to cry. He can dish it out but he can't take it).
Another interesting note, the article mentioned that as soon as you start standing up for yourself the narcissist will regain respect for you and suddenly wants you back. This happened as well on Friday.